Process of and apparatus for utilizing waste products of blast-furnaces



(No Model.) 2 SheetsSheet 1.

H. L. HARTENSTEIN. PROCESS OF AND APPARATUS FOR UTILIZING WASTE PRODUCTS 0P BLAST FURNACES.

Patented Jan.4,1898. W13

2 Sheets 2' del.)

H. L. HARTENSTEIN. PROGESS OF AND APPARATUS FOR UTILIZING WASTE PRODUCTS 01 LAST FURNACES.

Patented Jan.

UNITED STATES PATENT Orricn.

HERMAN L. I'IARTENSTEIN, OF BELLAIRE, OlIIO.

PROCESS 0F AND APPARATUS FOR UTILIZING WASTE PRODUCTS 0F BLAST-FURNACES.

SPECIFICATION forming part of Letters Patent No. 596,704, dated January 4, 1898.

Original application filed October 2'7, 1896, Serial No. 610,245.

To all whom it may con ern:

Be it known that I, HERMAN L. HARTEN- STEIN, a citizen of the United States, residing at Bellaire,in the county of Belmont and State of Ohio, have invented a new and useful Improvement in Processes of Utilizing the aste Products of a Blast-Furnace and Apparatus for Treating the Same, of which the following is a specification.

The subject of this application is divided out of my application, Serial No. 610,245, filed October 27, 1896. I

The object of my invention is so to dispose of blast-furnace slag as to produce therefrom a valuable commercial material useful for the manufacture of acetylene gas and other high-grade hydrocarbon gases and for various chemical and manufacturing processes, and incidentally to solve the problem of ridding blast-furnace plants of the ever-increasing incubus of slag and reduce the cost of manufacturing iron and steel.

To this end my invention consists in mixing with the slag, either in a molten condition or in a solid condition and afterward melting it, a suitable proportion of carbonaceous material, injecting into the molten mass a suitable reducing -gas for its heat enhancing quality, such as the gas evolved from the materials under treatment in the converter, and subjecting the molten slag with its admixture of carbonaceous material to the fusing action of an electric current by including it in the circuit thereof.

An average sample of blast-furnace slag produced in the manufacture of Bessemer iron shows the composition to be about as follows: lime, fifty to fifty-five per cent; silica, twenty-five to twentyeight per cent; alumina, sixteen to eighteen per cent, and a small proportion. of other elements, varying according to the ore and limestone used in the furnace.

By my treatment of the slag the oxygen is expelled from it and the calcium, silicon, and aluminium are combined with the carbon.

My invention further consists in the general as also in the more specific construction of the apparatus 1 have devised as best adapted for use in practicing my improved process,

Divided and this application filed February 9, 1897. Serial No. (No model.)

and which is illustrated in the accompanying drawings, in which Figure 1 is a view in cross-sectional elevation, partly-broken, of an apparatus suitable for use in practicing my invention; Fig. 2, a view of the same in sectional side elevation; Fig. 3, a bottom plan view of the converter with the pipe-inclosing box removed; Fig. 4, a cross-sectional view of a coke-feeding detail; and Figs. 5, 5", 5 and 5 are sectional views of the converter-chamber, showing it in the different positions to which it is adjusted in use.

A is a converter-chamber formed with the straight side walls 0* and end walls a", the lat ter flaring from a rounded base 0' which conneets them, the walls 1" being connected from their outer ends by a top formed of three sections, 0' 1", and 0- in angular relation to each other, and between the top section 4' and the end wall 0" the spout-opening q is formed. The shell of the converter-chamber may be formed of metal lined with refractory material, as indicated, the refractory lining, which I prefer to form of fire-clay, affording both a heat and an electric insulator. For convenience of access to the interior of the chamber A, as for repairing linings, renewing the carbon slabs hereinafter described, and the like, the wall-sections-r and 0'' should be removable and fastened together and to the respectively adjacent parts of the shell by bolts and keys or other means that will permit expeditious separation of the removable wall-seotions.

The terms base and top above employed are applied to the relative parts of the converter-chamber in the position in which it is shown in Fig. 5, being its initial position, or that in which it receives the charge.

The inner construction of the chamber A forms therein the three compartments 1), p, and 13 the firstnamed being the slag-receivin g compartment, the second the mixing-cont partment, and the third the electric-treatment compartment. The compartment 13 contains electrodes 0 and 0, preferably in the form of carbon slabs, which are let into grooves (not shown) in the lining of the compartment,

through the base of which are connected with the respective electrodes the insulated terminal wires to and 10, (see Fig. 2,) leading from the poles of a suitable electric generator Dsay a dynamo-electric machine.

The converter-chamber A is supported on hollow trunnions n and 12, respectively, eX- tending from its opposite sides through bearings at the upper ends of suitable standards on and m, and the trunnions carry near their outer ends the cog-wheels land Z, Fig. 1, to be engaged by suitable rack mechanism (not shown, but such as is commonly used in steelmills) for turning the chamber on its trunnions, as hereinafter described.

The base of the mixing-compartment p is pierced by feed-tubes 7b, of refractory material, such as fire-clay, each of which contains a pair of diaphragms h h of the same material as the feed-tubes, reaching short of its base to subdivide the tube into a number of passages for the better distribution of the material which is blown through them, as hereinafter described. These tubes thus form twyers.

B and O are pipes, the one leading from a supply (not shown) of gas under pressure and the other from the same source or from an air-blower (not shown) through the trunnions n and n, in which the pipes are divided, as indicated in Fig. 1, to permit turning with the converter-chamber the depending sections of the pipes, which are connected by branches iwith the twyers. A removable box F covers the base of the section 0- to protect the pipes and twyers from injury.

In the horizontal stationary portion of each pipe it is slotted longitudinally, the slot 9 (shown in Fig. 4:) being inclosed by a hopper H, rising from the pipe and containing a rotary fluted cylinder ll, journaled in the base portion of the hopper to extend lengthwise of and cover the slot g, and provided on the outer end of its stem f with a pulley f, through the medium of which to drive the fluted cylinder and cause it to feed with regularity into the pipe through its slot the carbonaceous material (coke) E contained in the hopper. The cylinders H so closely cover the respective slots in the pipes as to prevent escape of gas from the latter.

To start the apparatus, it is preparatorily heated by admitting gas into the converterchamber and igniting it, as by throwing in a handful of burning wood or shavings. lVhen the chamber has been sufficiently heated, the gas is turned off and the chamber is brought to the position in which it is shown in Fig. 5, in which molten slag is poured through the opening 1 into the compartment p. The gas is then slowly turned on and the coke-feeding mechanism is started and is continued in operation under the full pressure of the gassupply, which is thus employed as the vehicle for forcing the pulverulent carbonaceous material into the molten slag in addition to its function of enhancing the heat thereof. While the required quantity of the coke (say about one part to three parts of the slag) is being fed, the operation requiring not more than, say, five minutes, the chamber A is slowlyturned on its trunnions from the position in which it is represented in Fig. 5 to that in which it is represented in Fig. 5 and back again to agitate the materials and enhance their mixture. In this manner the charge of molten slag is caused to flow into the mixing-chamber p and becomes thoroughly impregnated throughout its entire mass with innumerable particles of the coke. It may be determined by spectroscopic observation of the carbon-lines of the converterfiame when the mixing has proceeded far enough.

It should be stated that the only use for an air-blast, hereinbefore referred to, is when or if the supply of gas shall be defective, in which event the air maybe used in conjunction with the pulverized coke for promoting combustion of the latter to maintain the molten condition. of the slag or to restore lost heat.

0n completing the mixing with the molten slag of the carbonaceous material the elec tric current is turned on, the gas-pressure is turned off, and the converter-chamber is swung to the position in which it is represented in Fig. 5 ,whereby the material is run into the compartment 29 The composition of blastfurnace slag renders it highly resistant to electricity; but by mixing with it the carbonaceous material, which is a good conductor of electricity, and interposin g in the circuit the mass of the mixture the latter is rendered conductive, but presents to the passage of the current the resistant property of the slag between adjacent particles of the coke contained therein ,whereby innumerable arcs are formed throughout the mass for generating the great intensity of heat requisite for the conversion of the mixture into the product of my improved process. Thus the medium (carbonaceous material) of conversion also aii'ords the medium for transmission of the current through the mass to be converted to generate the necessary intensity of heat to effect the conversion. 4

It takes about twenty min utes to thoroughly carburet the slag, after which the current is turned off and the chamber A is swung to the position in which it is represented in Fig. 5 to discharge the molten product, which may be cast into ingots or in molds of any desired size and shape. The converter is then ready to be used over again by returning it to its initial position, in which it is represented in Fig. 5, to receive another charge of molten slag.

\Vhat I claim as new, and desire to secure by Letters Patent, is-

1. The process of utilizing the waste prodnot of ablast-furnace, which consists in bringing slag to a condition suitable for admixture with carbonaceous materiahmixing therewith a suitable proportion of such material, injecting a reducing-gas into the mixture While in a molten condition and subjecting the molten slag with its admixture to the action of an electric current by including it in the circuit thereof, substantially as described.

2. The process of utilizing the waste product of a blast-furnace, which consists in mixing with molten slag a suitable proportion of carbonaceous material, injecting a reducinggas into the mixture and subjecting the molten slag with its admixture to the action of an electric current by including it in the circuit thereof, substantially as described.

3. The process of utilizing the waste product of a blast-furnace, which consists in mixing with molten slag a suitable proportion of pulverulent carbonaceous material, injecting a reducing-gas into the mixture and agitating it to enhance the impregnation of the slag with said carbonaceous material and subjecting the mixture to the action of an electric current by including it in the circuit thereof, substantially as described.

4. In an apparatus for converting blast-furnace slag, a rotatably-supported converterchamberhaving an opening and provided with a slag-receiving portion, a mixing portion and an electric-treatment portion, said portions having intercoinmunication, a partition between the mixing portion and the electrictreatment portion, electrodes in said electrictreatment portion, and terminal wires leading from a suitable electric generator to said electrodes, substantially as described.

5. In an apparatus for converting blast-furnace slag, the combination of arotatably-supported converter-chamber having an opening and provided with a mixing portion and an electric-treatment portion containing electrodes having electrical connections, and provided also with 'twyers, a blast-pipe leading to said twyers and provided with a slot, a hopper seated over said slot, and an agitating device supported in the hopper and adjacent to said slot, substantially as described.

6. In an apparatus for converting blast-furnace slag, the combination of a converterchamber A supported on trunnions and provided with an opening q, a receiving portion 19, a mixing portion 19, and an electric-treatment portion 19 said portions having intercomrnunication, electrodes 0 and 0 in the por tion p having electrical connections, twyers leading into the portion 17, a divided blastpipe leading through a trunnion to said twyers and provided with an opening g, a hopper H seated over the opening in said pipe, and a fluted cylinder H rotatably supported in the hopper and covering said opening, substantially as described.

HERMAN L. HARTENSTEIN.

In presence of M. S. MACKENZIE, R. T. SPENCER. 

